I agree, I don't think its anything so widespread or macabre as that.
However, something I do take into account is that most of the experts are experts in areas other than terrorism. It is in their best interest to speak from their knowledge base. Also, I have not heard many completely discount terrorism as a possibility. Especially since every other comparison they can make (i.e. serial killers, crazy right wing nuts, spree killers) involves an escalation of activity (killings get closer together or happen in multiples). This episode began with an attention-getting event (the first 5 deaths) and has seriously de-escalated since then (instead of hours, going days between shootings).
A psychopath is like a thrill adict—he or she requires an increasing amount of "comfort" for whatever is driving him or her. This is true in most cases. However, this assassin is so far out of the normal sociopathic or psychopathic profile . . . There is nothing predictable about him/her except unpredictability.
The coldness with which he targets people . . . the cleanliness of the assassin MO—removed from the victim. Distanced from the act. It is almost like he's doing a job or carrying out some sort of crusade. If we (freedom loving Americans) view American military snipers as heroes for saving our troops in times of danger—could it be that this person is acting as a hero for another cause? What is that cause? What could be so important that killing men, women, and children in cold blood would warrant his actions. As far as we can tell, this is not personal. This is mission-driven. What is this person's mission?
Just some thoughts. This is unprecedented, LS, none of us really knows what is going on. We can only make guesses. And yours is as good as mine.